The overarching mission of the MB/MG Core is assist investigators seeking to discover the molecular bases underlying obesity and its comorbidities. To achieve this mission, the Core performs studies in humans and rodents to identify mutations in candidate genes as well as rodent studies to define the functions of candidate genes by genetic manipulations using transgenic methodologies, the MB/MG Core makes available to biomedical investigators a wide range of methodologies and reagents relevant to understanding me molecular physiology of obesity and energy metabolism in animals and humans. This core applies molecular genetic and molecular biological techniques to the mapping, cloning and functional characterization of genes related to obesity and its comorbidities. The services of this Core are available to investigators new to obesity research, as well as to investigators working on obesity-related projects that can be enriched and extended by the use of the expertise and facilities of this core. This Core operates in 2 collaborating sites: Columbia University (R. Leibel) and AECOM (S. Chua). In general, techniques and services related to studies in humans are located at the former, and those related to rodents at tne fatter. However, this distinction is not rigid, and there is a lot of crossover between the sites. Services fndude a full range of capabilities in DNA and RNA isolation, sequencing, manipulation and quantification; experimental design and execution of gene/QTL-mapping studies in rodents and humans; maintenance of novel mouse genetic models of obesity; and design and execution of mouse transgenesis experiments.